Kitin üzerine tekli veya ikili cu(II) ve cu(II) adsorpsiyonu

The adsorption of single and binary Cu(II) and Cd(II) onto chitin was examined in the batch system. The influence of primary pH, temperature, and initial single and binary metal concentrations on the adsorption equilibrium and kinetics of every constituent, together single and binary combination were studied. The equilibrium uptakes of single and binary Cu(II) and Cd (II) were increased with increasing temperature up to 40 oC. The chitin selectively adsorbed single Cu(II), binary Cu(II) and Cd(II) ions at pH= 4.5, while single Cd(II) ions were adsorbed by the chitin at pH 5.0. The Freundlich, Langmuir, and Tempkin adsorption models were utilized for the mathematical definition of the adsorption equilibrium and isotherm constants were assessed at different temperatures (20, 30 and 40 oC). The single and binary constituent system was well defined with the Langmuir isotherm model. The maximum Cu(II) and Cd(II) adsorption capacity of chitin calculated Langmuir model were as high as 5.80 and 6.87 mg/g for single Cu(II) and Cd(II), 6.01 and 8.41 mg/g for binary Cu(II) and Cd(II), respectively. The results showed that adsorption of single and binary Cu(II) and Cd(II) onto chitin were endothermic and natural. Kinetics studies were carried out in the temperarure range of 20–40 oC. The stimulation energies of the adsorption were determined as 1.34 and 2.55 kJ mol−1 for single Cu(II) and Cd(II), respectively. Utilizing the thermodynamic equilibrium coefficients obtained at different temperature, the Gibbs free energy changes −3.78 k/J mol for single Cu(II) and −4.15 kJ /mol for single Cd(II) at 40 oC, enthalpy changes 15.38 kJ/ mol for Cu(II) and 20.13 kJ/ mol for Cd(II) of adsorption were also determined, respectively. The pseudo-first order, pseudo-second order and intraparticle diffusion models were applied to the kinetic data. The pseudo-second order kinetic fitted well model and the presence of intraparticle diffusion mechanism was specified. Thermodynamic examined presented an endothermic, dissociative, natural and a physical adsorption operating among the metal ions and the chitin. In addition, a synergistic influence of two metals has been noticed and examined in the binary metal system. The results signify that not only the concurrent attendance of the two metals does not lessen the adsorption ability, but also improves their removal from the emanation.